阅读说明：本技术 负电压轨 (Negative voltage rail ) 是由 S·J·克里斯蒂安松 于 2020-02-20 设计创作，主要内容包括：本发明构思涉及一种负轨生成器,该负轨生成器临时地自生成负电压轨以将跨发光二极管(LED)的电压差增加到大于可用的正电源电压。如此,电压差提供了足够的净空以超过以恒定电流导通LED所需的最小正向电压。在一个示例中,负轨生成器可以包括电容器、二极管钳位器和晶体管。负轨生成器和LED可通过共用PWM信号来同步地操作。负电压轨可在无需添加开关模式电源(SMPS)或电荷泵的情况下被生成。(The present inventive concept relates to a negative rail generator that temporarily self-generates a negative voltage rail to increase a voltage difference across a Light Emitting Diode (LED) to be greater than an available positive supply voltage. In this manner, the voltage difference provides sufficient headroom to exceed the minimum forward voltage required to turn on the LED at a constant current. In one example, the negative rail generator may include a capacitor, a diode clamp, and a transistor. The negative rail generator and the LED may be operated synchronously by a common PWM signal. The negative voltage rail may be generated without the addition of a Switched Mode Power Supply (SMPS) or charge pump.)